Technical Field
[0001] The present disclosure relates to a tensioning device for a chain driven jaw system
in a package filling machine and related method.
Background
[0002] It is known that a chain in a chain driven system for a filling machine needs to
be tensioned to keep rollers of jaws and counter-jaws in contact with cams for the
jaws. One such arrangement is disclosed in
EP0887269 disclosing, in relation to e.g. figure 2, that along portions P3, Q3, chains 15,
27 cooperate with respective pairs of tensioners 56 for tensioning the chains to ensure
rollers 52, 53 of jaws 12 and counter-jaws 13 are maintained in contact with respective
cams 50, 51. Each tensioner 56 comprises a movable shoe 57 hinged about a horizontal
axis to a support fixed to wall 6 or 7. On the face facing away from wall 6 or 7,
shoe 57 comprises two side by side rolling tracks 60, 61, which, by virtue of a spring
59, cooperate with respectively rollers 52 and 53 of jaws 12 or counter-jaws13.
[0003] An issue with such arrangement as e.g. disclosed in
EP0887269 is that the rollers that are driven by chains are exposed to a high degree of friction
and hammering on the chains by the arrangement of the tensioners. Further, a workload
for a servo motor driving the chains increases due to e.g. the increased friction,
and the arrangement would also create extra wear on the fixed cam due to the impact
force of the chains.
[0004] Hence, an improved tensioning device, jaw system, filling machine and method would
be advantageous and in particular allowing for avoiding more of the above-mentioned
problems and compromises, including providing for reducing the wear in a chain driven
jaw system and reducing the workload on the associated motor drive.
Summary
[0005] Accordingly, examples of the present invention preferably seek to mitigate, alleviate
or eliminate one or more deficiencies, disadvantages or issues in the art, such as
the above-identified, singly or in any combination by providing a device according
to the appended patent claims.
[0006] According to a first aspect a tensioning device for a chain driven jaw system in
a package filling machine is provided. The chain driven jaw system has a fixed cam
and a chain as a follower. The tensioning device comprises a chain tensioning element
shaped and angled so to receive the chain on an outer surface thereof configured to
be directed away from a center of the chain driven jaw system, wherein the chain tensioning
element comprises a pivot connection, and wherein the chain tensioning element is
configured to be integrated with the fixed cam at the pivot connection such that the
chain tensioning element abuts the fixed cam at the pivot connection and can move
to tension the chain.
[0007] According to a second aspect a chain driven jaw system for a package filling machine
is provided. The chain driven system comprises at least one fixed cam, a chain as
a follower, and at least one tensioning device, wherein the tensioning device comprises,
a chain tensioning element shaped and angled so to receive the chain on an outer surface
directed away from a center of the chain driven jaw system, wherein the chain tensioning
element comprises a pivot connection, and wherein the chain tensioning element is
integrated with the fixed cam at the pivot connection such that the chain tensioning
element abuts the fixed cam at the pivot connection and can move to tension the chain.
[0008] According to a third aspect a filling machine is provided comprising a chain driven
jaw system according to the second aspect or a tensioning device according to the
first aspect.
[0009] According to a fourth aspect a method is provided for tensioning a chain in a chain
driven jaw system for a package filling machine having a cam and a chain as a follower.
The method comprises providing a chain tensioning device comprising a chain tensioning
element shaped and angled so to receive the chain on an outer surface directed away
from a center of the chain driven jaw system, wherein the chain tensioning element
is configured to be integrated with the fixed cam at a pivot connection such that
the chain tensioning element abuts the fixed cam at the pivot connection and can move
to tension the chain, and tensioning the chain with the tensioning device.
[0010] Further examples of the invention are defined in the dependent claims, wherein features
for the second and third aspects of the disclosure are as for the first aspect mutatis
mutandis.
[0011] Some examples of the disclosure provide for reduced wear in a chain driven jaw system.
[0012] Some examples of the disclosure provide for reduced workload on the motor drive of
a chain driven jaw system.
[0013] Some examples of the disclosure provide for reducing the vibrations in a chain driven
jaw system.
[0014] Some examples of the disclosure provide for a smoother motion of the chain in a chain
driven jaw system.
[0015] Some examples of the disclosure provide for a more predictable and efficient maintenance
schedule of a chain driven jaw system.
[0016] It should be emphasized that the term "comprises/comprising" when used in this specification
is taken to specify the presence of stated features, integers, steps or components
but does not preclude the presence or addition of one or more other features, integers,
steps, components or groups thereof.
Brief Description of the Drawings
[0017] These and other aspects, features and advantages of which examples of the invention
are capable of will be apparent and elucidated from the following description of examples
of the present invention, reference being made to the accompanying drawings, in which;
Figs. 1a-b are schematic illustrations of a tensioning device and a chain driven jaw
system according to examples of the disclosure;
Fig. 2 is a schematic illustration of a tensioning device in a chain driven jaw system
according to examples of the disclosure;
Fig. 3 is a schematic illustration, in a perspective view, of a tensioning device
in a chain driven jaw system according to examples of the disclosure;
Fig. 4 is a schematic illustration, in a perspective view, of tensioning devices in
a chain driven jaw system according to examples of the disclosure;
Fig. 5a is a flowchart of a method of tensioning a chain in a chain driven jaw system
according to examples of the disclosure; and
Fig. 5b is another flowchart of a method of tensioning a chain in a chain driven jaw
system according to examples of the disclosure.
Detailed Description
[0018] Specific examples of the invention will now be described with reference to the accompanying
drawings. This invention may, however, be embodied in many different forms and should
not be construed as limited to the examples set forth herein; rather, these examples
are provided so that this disclosure will be thorough and complete, and will fully
convey the scope of the invention to those skilled in the art. The terminology used
in the detailed description of the examples illustrated in the accompanying drawings
is not intended to be limiting of the invention. In the drawings, like numbers refer
to like elements.
[0019] Fig. 1 a is a schematic illustration of a tensioning device 100 for a chain driven
jaw system 200 in a package filling machine. The chain driven jaw system 200 has a
fixed cam 101 and a chain 102 as a follower. The fixed cam 101 has a curved outer
track along which the chain 102 (indicated with dashed lines) is transported via rollers.
The tensioning device 100 comprises a chain tensioning element 103 shaped and angled
so to receive the chain 102 on an outer surface 104 thereof configured to be directed
away from a center (C) of the chain driven jaw system 200. Figs. 2 and 3 are schematic
illustrations of the chain tensioning element 103 in a detailed side view and in a
perspective view, respectively. The surface 104 is thus arranged to abut the chain
102 when transported along the outer track of the fixed cam 101. The chain tensioning
element 103 comprises a pivot connection 105, around which the chain tensioning element
103 may pivot. The chain tensioning element 103 is configured to be integrated with
the fixed cam 101 at the pivot connection 105 such that the chain tensioning element
103 abuts the fixed cam 101 at the pivot connection 105 and can move to tension the
chain 102. By having the chain tensioning element 103 configured to be integrated
with the fixed cam 101, i.e. in abutment with the fixed cam 101 at the pivot connection
105, the chain 102 can move smoothly onto the cam 101 from the chain tensioning element
103, while being sufficiently tensioned. In contrast, tensioning elements of prior
art being separated from the cam, so that the associated chain forms an unsupported
bridge between the chain tensioning element and the cam, create a more erratic and
less controlled path of motion of the chain, which an increase risk of damaging vibrations
and increased wear on the components. Thus, having the tensioning element 103 integrated
with the fixed cam 101, allowing the outer surface 104 to transition directly to the
outer track of the cam 101, provides for continuous support for the chain 102 and
reduced vibrations and wear. The reduced vibrations provide also for decreasing the
workload on the motor drive of the chain 102, and increased life time or longer service
intervals, since the chain 102 will slide more smoothly and be less prone to hitting
anything which otherwise may lead to unnecessary accelerations and/or decelerations
of the motor. As illustrated in e.g. Fig. 1a and 2, the pivot point 105 may be integrated
to the fixed cam 101 directly adjacent the outer track of the fixed cam 101, so that
there will be a smooth transition between the chain tensioning element 103 and the
outer track of the cam 101, as explained in more detail below.
[0020] The chain tensioning element 103 may have a curved outer surface 104 on which the
chain 102 slides on, as shown in the example of e.g. Fig. 1a. Having a curved outer
surface 104 allows the chain tensioning element 103 to follow the path of the chain
102 so that a minimum of resistance is introduced by the chain tensioning element
103, but at the same time gradually tensions the chain 102.
[0021] Turning to Fig. 2, the pivot connection 105 may be arranged at a first end 106 of
the tensioning element 103. The outer surface 104 may extend to the first end 106
and the pivot connection 105 thereof, to form an outer pivot surface 104' of the chain
tensioning element 103. As elucidated above, the outer pivot surface 104', at the
first end 106, may be arranged to form a smooth direct transition to an outer cam
surface 107' of a first portion 107 of the fixed cam 101 to which the chain tensioning
element 103 is configured to be integrated, via the pivot connection 105. Fig. 2 schematically
shows the outer pivot surface 104' arranged to form a smooth direct transition to
the outer cam surface 107' of the first portion 107, providing for reducing the vibrations
and wear of the chain 102, cam 101 and chain tensioning element 103 during operation.
Accordingly, this also allows for the chain driven jaw system 200 to be operated at
a higher speed, without risk of excessive wear, for increasing the throughput of the
system 200 and filling machine (not shown) in which the tensioning device 100 and
system 200 may be arranged.
[0022] A tangential line 108 of the outer pivot surface 104' may be configured to be aligned
in parallel with a tangential line 109 of the outer cam surface 107' of the first
portion 107, in at least one position of the chain tensioning element relative to
the first portion 107, as schematically illustrated in Fig. 2. Such arrangement allows
for a smooth transition between the outer pivot surface 104' outer cam surface 107',
also when the tension, i.e. the angle of the chain tensioning element 103, is varied
since it is conceivable that the tangential lines 108, 109, may be parallel in a default
calibrated position, and only small variations in the mentioned angle may be needed
to further adjust the tension.
[0023] The outer pivot surface 104' may be configured to form an uninterrupted transition
to the outer cam surface 107' of the fixed cam 101 so that the chain 102 is continuously
supported when bridged across the outer pivot surface 104' and the outer cam surface
107'. There may accordingly be no gaps between the outer pivot surface 104' and the
outer cam surface 107', providing for improved support of the chain 102 and reduced
risk of vibrations.
[0024] The chain tensioning element 103 may comprise a second end 110 ending freely, opposite
the first end 106. The second end 110 may be configured to receive the chain 102 for
subsequent guiding across the outer surface 104 to the first end 106. By having the
second end 110 ending freely the chain 102 can slide onto the second end 110 more
or less independent of how the chain 102 moves and then be guided into the correct
position at the other first end 106 onto the cam 101 again.
[0025] The chain tensioning element 103 may comprise a spring 120 configured to push the
chain tensioning element 103 outward from the center (C) of the chain driven jaw system
200. The spring 120 may be arranged adjacent the pivot connection 105 and the first
portion 107 of the fixed cam 101 to which the chain tensioning element 103 is configured
to be integrated. By having a spring 120 pushing the chain tensioning element 103
towards the chain 102, the chain 102 can be tensioned but at the same time the spring
120 allows for some flexibility in some force directions. Having the spring 120 configured
to be arranged adjacent the pivot connection 105 and the first portion 107 of the
fixed cam 101 provides for the benefits discussed above with the chain tensioning
element 103 integrated with the first portion 107 while allowing for the mentioned
tensioning. The spring 120 may be integrated with the pivot connection 105, providing
for a tensioning device 100 with fewer components. Having the spring 120 connected
between the first and second end 106, 110, it is possible to vary the effect of the
spring 120 to optimize the tensioning.
[0026] A chain driven jaw system 200 for a package filling machine is provided. The chain
driven system 200 comprises at least one fixed cam 101 and chain 102 as a follower,
as explained above. The chain driven jaw system 200 comprises at least one tensioning
device 100, 100'. The tensioning device 100, 100', comprises a chain tensioning element
103 shaped and angled so to receive the chain on an outer surface 104 directed away
from a center (C) of the chain driven jaw system 200. The chain tensioning element
103 comprises a pivot connection 105, and the chain tensioning element 103 is integrated
with the fixed cam 101 at the pivot connection 105 such that the chain tensioning
element 103 abuts the fixed cam 101 at the pivot connection 105 and can move to tension
the chain 102. The chain driven jaw system 200 thus provides for the advantageous
benefits as described above in relation to the tensioning device 100 and Figs. 1 -
3. The chain driven jaw system 200 may comprise at least two tensioning devices 100,
100', arranged parallel to each other, as schematically illustrated in Fig. 4. A chain
driven jaw system 200 comprising at least two of the chain tensioning devices 100,
100', allows for a plurality of chains 101 to be run smoothly at the same time parallel
to each other and allows for a more complex jaw system 200.
[0027] The chain driven jaw system 200 may comprise a path 112 along which the chain 102
is transported. The path 112 comprises a first section 113 along which the chain 102
is in abutment with the fixed cam 101, and a second section 114 along which the chain
102 is in abutment with the chain tensioning element 103, as schematically illustrated
in Fig. 1 b. I.e. the path 112 follows the outer surface or outer track of the fixed
cam 101 and the chain tensioning element 103. The path 112 comprises a first longitudinal
portion 115 comprising at least part of the first and second sections 113, 114, being
substantially parallel and aligned end to end in the longitudinal direction, in at
least one position of the chain tensioning element 103 relative to the first portion
107. Hence, the chain 102 may form a bridge portion 116 between the first and second
sections 113, 114, along the first longitudinal portion 115 so that the bridge portion
116 extends across the pivot connection 105. Such arrangement allows for a smooth
transition between the outer pivot surface 104' outer cam surface 107', also when
the tension, i.e. the angle of the chain tensioning element 103, is varied since it
is conceivable that the first and second sections 113, 114, may be parallel in a default
calibrated position, and only small variations in the mentioned angle may be needed
to further adjust the tension.
[0028] As explained, the pivot connection 105 may be arranged at a first end 106 of the
chain tensioning element 103. The outer surface 104 may extends to the first end 106
and the pivot connection 105 thereof, to form an outer pivot surface 104' of the tensioning
element 103. The outer pivot surface 104', at the first end 106, may be arranged to
form a smooth transition to an outer cam surface 107' of a first portion 107 of the
fixed cam 101 to which the chain tensioning element 103 is integrated, via the pivot
connection 105.
[0029] And as further elucidated, a tangential line 108 of the outer pivot surface 104'
may be aligned in parallel with a tangential line 109 of the outer cam surface 107'
of the first portion 107, in at least one position of the tensioning element 103 relative
to the first portion 107.
[0030] The first portion 107 of the fixed cam 101 may be arranged so that a distance between
the first portion 107 and the center (C) of the chain driven jaw system 200 is shorter
than a distance from the first portion 107 to the closest of the opposite ends 117,
118, of the chain driven jaw system 200 (see Fig. 1 a), relative to the first portion
107, along a longitudinal direction 119 in which the chain tensioning element 103
extends. Thus, the first portion may be arranged adjacent, or closer to, the center
(C) than any of the opposite ends 117, 118. Also, since the pivot connection 105 is
integrated with the first portion 107, the same arrangement applies to the pivot connection
105, i.e. the pivot connection 105 may be arranged adjacent, or closer to, the center
(C) than any of the opposite ends 117, 118. Since the chain tensioning element 103
is arranged to the fixed cam 101 at the pivot connection 105, at allows for the chain
102 to be supported along the full distance of the cam 101 between the opposite ends
117, 118, thereof, with no interruptions adjacent the center (C).
[0031] A filling machine (not shown) is provided comprising a chain driven jaw system 200
as described above in relation to Figs. 1 - 4, and/or the filling machine comprises
a tensioning device 100 as described above in relation to Figs. 1 - 4. The filling
machine thus provides for the advantageous benefits as described above in relation
to the tensioning device 100 and the chain driven jaw system 200, and Figs. 1 - 4.
The filling machine may thus be operated with a reduced amount of vibrations and/or
wear of its components, even at higher operating speeds.
[0032] Fig. 5a illustrates a flow chart of a method 300 of tensioning a chain in a chain
driven jaw system 200 for a package filling machine. The order in which the steps
of the method 200 are described and illustrated should not be construed as limiting
and it is conceivable that the steps can be performed in varying order. A method 200
is thus provided comprising providing 301 a tensioning device 100 comprising a chain
tensioning element 103 shaped and angled so to receive the chain on an outer surface
104 directed away from a center (C) of the chain driven jaw system 200. The chain
tensioning element 103 is configured to be integrated with the fixed cam 101 at a
pivot connection 105 such that the chain tensioning element 103 abuts the fixed cam
101 at the pivot connection 105 and can move to tension the chain 102. The method
300 comprises tensioning 302 the chain 102 with the tensioning device 100. The method
300 thus provides for the advantageous benefits as described above in relation to
the tensioning device 100 and the chain driven jaw system 200, and Figs. 1 - 4. Thus,
by using the tensioning device 100 the tension on the chain 102 can be guaranteed
and at the same time a smoother transition from the chain tensioning element 103 on
to the fixed cam 101 is provided.
[0033] Fig. 5b illustrates a further flow chart of a method 300' of tensioning a chain 102
in a chain driven jaw system 200 for a package filling machine. The order in which
the steps of the method 300' are described and illustrated should not be construed
as limiting and it is conceivable that the steps can be performed in varying order.
The method 300' may thus comprise the steps of the method 300 and also tensioning
a plurality of chains 102 by using a plurality of tensioning devices 100, 100'.
[0034] The present invention has been described above with reference to specific examples.
However, other examples than the above described are equally possible within the scope
of the invention. The different features and steps of the invention may be combined
in other combinations than those described. The scope of the invention is only limited
by the appended patent claims.
[0035] More generally, those skilled in the art will readily appreciate that all parameters,
dimensions, materials, and configurations described herein are meant to be exemplary
and that the actual parameters, dimensions, materials, and/or configurations will
depend upon the specific application or applications for which the teachings of the
present invention is/are used.
1. A tensioning device (100) for a chain driven jaw system in a package filling machine,
the chain driven jaw system has a fixed cam (101) and a chain (102) as a follower,
the tensioning device comprises,
a chain tensioning element (103) shaped and angled so to receive the chain on an outer
surface (104) thereof configured to be directed away from a center (C) of the chain
driven jaw system, wherein the chain tensioning element comprises a pivot connection
(105), and wherein the chain tensioning element is configured to be integrated with
the fixed cam at the pivot connection such that the chain tensioning element abuts
the fixed cam at the pivot connection and can move to tension the chain.
2. A tensioning device according to claim 1, wherein the pivot connection is arranged
at a first end (106) of the tensioning element, the outer surface extends to the first
end and the pivot connection thereof, to form an outer pivot surface (104') of the
chain tensioning element, wherein the outer pivot surface, at the first end, is arranged
to form a smooth direct transition to an outer cam surface (107') of a first portion
(107) of the fixed cam to which the chain tensioning element is configured to be integrated,
via the pivot connection.
3. A tensioning device according to claim 2, wherein a tangential line (108) of the outer
pivot surface is configured to be aligned in parallel with a tangential line (109)
of the outer cam surface of the first portion, in at least one position of the chain
tensioning element relative to the first portion.
4. A tensioning device according to claim 2 or 3, wherein the outer pivot surface is
configured to form an uninterrupted transition to the outer cam surface of the fixed
cam so that the chain is continuously supported when bridged across the outer pivot
surface and the outer cam surface.
5. A tensioning device according to any of claims 1 - 4, wherein the chain tensioning
element comprises a second end (110) ending freely, opposite the first end, and wherein
the second end is configured to receive the chain for subsequent guiding across the
outer surface to the first end.
6. A tensioning device according to claim 2, wherein the chain tensioning element comprises
a spring configured to push the chain tensioning element outward from the center of
the chain driven jaw system, and wherein the spring is arranged adjacent the pivot
connection and the first portion (107) of the fixed cam to which the chain tensioning
element is configured to be integrated.
(a distance from the spring and the pivot connection is smaller than a distance between
the spring and a tip (111) of a second end (110) of the tensioning element, opposite
the pivot connection.)
7. A chain driven jaw system (200) for a package filling machine, the chain driven system
comprises
at least one fixed cam (101) and chain (102) as a follower,
at least one tensioning device (100, 100'), wherein the tensioning device comprises,
a chain tensioning element (103) shaped and angled so to receive the chain on an outer
surface (104) directed away from a center (C) of the chain driven jaw system, wherein
the chain tensioning element comprises a pivot connection (105), and wherein the chain
tensioning element is integrated with the fixed cam at the pivot connection such that
the chain tensioning element abuts the fixed cam at the pivot connection and can move
to tension the chain.
8. Chain driven jaw system according to claim 7, comprising a path (112) along which
the chain is transported, the path comprises a first section (113) along which the
chain is in abutment with the fixed cam, and a second section (114) along which the
chain is in abutment with the chain tensioning element,
whereby the path comprises a first longitudinal portion (115) comprising at least
part of the first and second sections being substantially parallel, whereby, where
the chain forms a bridge portion (116) between the first and second sections, along
the first longitudinal portion, the bridge portion extends across the pivot connection.
9. Chain driven jaw system according to claim 7 or 8, wherein the pivot connection is
arranged at a first end (106) of the chain tensioning element, the outer surface extends
to the first end and the pivot connection thereof, to form an outer pivot surface
(104') of the chain tensioning element, wherein the outer pivot surface, at the first
end, is arranged to form a smooth transition to an outer cam surface (107') of a first
portion (107) of the fixed cam to which the chain tensioning element is integrated,
via the pivot connection.
10. Chain driven jaw system according to claim 9, wherein a tangential line (108) of the
outer pivot surface is aligned in parallel with a tangential line (109) of the outer
cam surface of the first portion, in at least one position of the tensioning element
relative to the first portion.
11. Chain driven jaw system according to claim 9 or 10, wherein the first portion of the
fixed cam is arranged so that a distance between the first portion and the center
of the chain driven jaw system is shorter than a distance from the first portion to
the closest of the opposite ends (117, 118) of the chain driven jaw system, relative
to said first portion, along a longitudinal direction (119) in which the chain tensioning
element extends.
12. Filling machine comprising a chain driven jaw system according to any of claims 7
- 11, or a tensioning device according to any of claims 1 - 6.
13. A method (300) of tensioning a chain in a chain driven jaw system (200) for a package
filling machine having a cam (101) and a chain (102) as a follower, the method comprises,
providing (301) a chain tensioning device comprising a chain tensioning element (103)
shaped and angled so to receive the chain on an outer surface (104) directed away
from a center (C) of the chain driven jaw system, wherein the chain tensioning element
is configured to be integrated with the fixed cam at a pivot connection (105) such
that the chain tensioning element abuts the fixed cam at the pivot connection and
can move to tension the chain, and
tensioning (302) the chain with the tensioning device.
14. Method according to claim 13 comprising tensioning (303) a plurality of chains by
using a plurality of tensioning devices.